Guerrilla’s Games’ Herman Hulst noted at a press event that Naughty Dog is not involved in Killzone 3. The information regarding destructible enviroments may also be false as well. What has been confirmed on the other hand, is the addition of a new “brutal melee system.”

I don’t think Naughty Dog getting involved is a reason to get my hopes up. Guerilla is a very good studio, and did amazing things with KZ2. I’m sure they’ll do a bang up job on KZ3, with or without Naughty Dog.